Rail re-profiling method and apparatus

ABSTRACT

A method of milling a profile of a railway rail comprises: rotating a milling cutter including a plurality of face mounted cutting inserts mounted about a periphery thereof; milling a railway rail with cutting edges of the cutting inserts rotating in a predetermined plane corresponding to at least a portion of a desired rail profile while controlling the depth of cut of the cutting inserts; traversing the railway rail with the milling cutter while milling the railway rail; and controlling the speed of traverse of the milling cutter along the railway rail.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a divisional application claiming priorityunder 35 U.S.C §120 to co-pending U.S. patent application Ser. No.13/841,026, filed on Mar. 15, 2013, which patent application is herebyincorporated herein by reference in its entirety.

BACKGROUND OF THE TECHNOLOGY Field of the Technology

The present disclosure generally relates to equipment and techniques formilling. The present disclosure more specifically relates to equipmentand techniques adapted for milling railway rails.

Description of the Background of the Technology

Railways networks are in use throughout the world for freight andtransit alike. Over time, railway rails become worn and irregularitiesmay arise, especially along the railhead profiles. Consequently,railways must be maintained by either replacing or re-profiling worn ordeformed rails. For example, rail re-profiling may be undertaken toaddress common rail deformities such as rail corrugation, which maycomprise short to long wavelengths. Corrugations are known to causenoise, vibrations, and premature wheel wear. Rail re-profiling may alsobe undertaken as part of a regular maintenance schedule aimed atextending the operational life of rails.

To minimize interference with rail traffic and to reduce labor costs, itis often advantageous to re-profile worn rails in situ. While in siture-profiling may avoid extended offline periods, present re-profilingstrategies comprising planing, grinding, and, more recently, peripheralmilling are generally slow and/or hazardous endeavors. For example, railgrinding may employ one or more grinding wheels mounted to a railgrinding vehicle. Rail grinding vehicles are known to producesignificant quantities of sparks during the grinding process, which maypresent a significant fire hazard along the railway at its periphery.Conventional rail re-profiling vehicles also are known to producechatter and may be unable to produce desirable smooth and continuousrailhead profiles. Certain conventional rail milling vehicles employperipheral milling techniques to mill a predetermined profile on therails. While presenting less fire risk than rail grinding vehicles, railmilling vehicles typically advance along the railway slowly and mayrequire that the railway be taken out of service for an extended period.Rail milling vehicles also may be unable to continuously mill rail. Forexample, peripheral milling cutters used on such vehicles are designedto form a specific railhead profile and, therefore, are unable toadequately adapt to changing rail conditions such as variations in therailhead profile, curves, or transitions (such as, for example, railwaygrade crossings). Consequently, the conventional rail milling processmay be slowed in order to adjust or replace milling cutters to match therail profile variations, adapt to changes in the condition of the rails,or address curves or transitions. In some instances, large sections ofrailway must be ignored or are inadequately milled due to variations ortransitions.

Given the foregoing drawbacks, it would be advantageous to developimproved techniques for rail re-profiling.

SUMMARY

According to one aspect of the present disclosure, a method of milling aprofile of a railway rail comprises: rotating a milling cutter includinga plurality of face mounted cutting inserts mounted about a peripherythereof; milling a railway rail with cutting edges of the cuttinginserts rotating in a predetermined plane corresponding to at least aportion of a desired rail profile while controlling the depth of cut ofthe cutting inserts; traversing the railway rail with the milling cutterwhile milling the railway rail; and controlling the speed of traverse ofthe milling cutter along the railway rail.

According to certain non-limiting embodiments, the method furthercomprises milling the railway rail with a plurality of milling cutters,each milling cutter including a plurality of face mounted cuttinginserts mounted about a periphery thereof. In such method, cutting edgesof the cutting inserts of each milling cutter are rotated in apredetermined plane corresponding to at least a portion of a desiredrail profile.

According to an additional aspect of the present disclosure, anapparatus for milling at least a portion of a desired profile on arailway rail in situ comprises: a milling cutter including a cutter bodycomprising a cutter face, wherein the milling cutter is rotatable abouta rotation axis; and a plurality of cutting inserts mounted around aperiphery of the cutter face. Each of the plurality of cutting insertscomprises a cutting edge extending a distance from the cutter face toengage and mill a profile segment on the railway rail. The rotation axisis substantially perpendicular to the plane of the profile segment to bemilled on the railway rail by the cutting inserts.

According to certain non-limiting embodiments, the apparatus furthercomprises a plurality of milling cutters, each milling cutter includinga cutter body rotatable about a rotation axis and a cutter face. Aplurality of cutting inserts are mounted around a periphery of thecutter face of each of the plurality of milling cutters, and each of theplurality of cutting inserts comprises a cutting edge extending adistance from the cutter face to engage a railway rail and mill asegment of a desired profile on the railway rail.

According to certain non-limiting embodiments, the apparatus maycomprise a rail vehicle on which are mounted the plurality of millingcutters. In certain embodiments, the plurality of milling cutters areindividually mounted to respective spindles, and each of the pluralityof milling cutters is individually positionable about a railway rail tomill a plurality of segments of a desired profile on the railway rail.

BRIEF DESCRIPTION OF THE DRAWINGS

The various embodiments of methods and apparatuses described herein maybe better understood by considering the following description inconjunction with the accompanying drawings.

FIG. 1A is a perspective view of a milling cutter according to variousembodiments disclosed herein;

FIG. 1B schematically illustrates a milling cutter positioned to engageand mill a railway rail according to various embodiments describedherein;

FIG. 2 schematically illustrates certain features of a milling cutteraccording to various embodiments described herein;

FIG. 3 is a table providing various parameters used to evaluate certainmilling cutter configurations as described herein;

FIG. 4 illustrates a milling insert used in certain testing conductedaccording to parameters listed in the table of FIG. 3;

FIGS. 5A-C schematically illustrate features of a milling cutteraccording to various embodiments described herein;

FIGS. 6A-C illustrate certain components of a milling cutter accordingto various embodiments described herein;

FIG. 7 is a semi-schematic view illustrating features of a millinginsert according to various embodiments described herein;

FIG. 8 illustrates the application of a conventional milling orientationand a climb milling orientation to the milling of railway railsaccording to various embodiments described herein;

FIG. 9 illustrates a milling cutter milling a railway rail according tovarious embodiments described herein;

FIG. 10 illustrates a milling cutter milling a railway rail according tovarious embodiments described herein;

FIG. 11 is a table providing various parameters used in evaluatingcertain milling cutters configurations as described herein;

FIG. 12A schematically illustrates a milling cutter contacting a railwayrail in an angled orientation according to various embodiments describedherein;

FIG. 12B illustrates various angled orientations of a milling cutterrelative to a railway rail according to various embodiments describedherein;

FIG. 13A is a table providing various parameters used in evaluatingcertain configurations of milling cutters as described herein;

FIG. 13B is a photographic depiction of cutting inserts used in testingdescribed herein;

FIG. 14A is a table providing various parameters used in evaluatingcertain milling cutter configurations as described herein;

FIG. 14B illustrates a rail re-profiled in testing described herein;

FIG. 15 is a table providing various parameters used in evaluatingcertain configurations of milling cutters as described herein;

FIG. 16 provides photograph depictions of various cutting inserts usedin testing described herein;

FIGS. 17A-17C schematically illustrate certain features of a millingcutter according to various embodiments described herein;

FIG. 18A is a table providing various parameters used in evaluatingcertain configurations of milling cutters as described herein;

FIG. 18B illustrates a test carriage including two milling cutters thatwas used in testing described herein;

FIGS. 19A-C illustrate various cutting inserts used in testing describedherein;

FIGS. 20A and 20B schematically illustrate certain features of a millingcutter according to various embodiments described herein; and

FIG. 21 schematically illustrates an arrangement of a plurality ofmilling cutters orientated about a railway rail to each define aseparate portion or region of the rail profile according to variousembodiments described herein.

DETAILED DESCRIPTION OF CERTAIN NON-LIMITING EMBODIMENTS

The present disclosure describes various embodiments of apparatuses,milling cutters, milling inserts, and milling methods for re-profilingrailway rails. In one embodiment, a milling cutter according to thepresent disclosure comprises a plurality of cutting inserts. The cuttinginserts may be positioned in one or more orientations proximate to arailway rail to be re-profiled. In certain forms, the milling cuttercomprises a cutter body configured to retain a plurality of cuttinginserts, for example, indexable cutting inserts, thereon. The millingcutter may traverse the railway rail while rotating about a centralaxis. Each of the plurality of cutting inserts may comprise a cuttingedge configured to engage the rail during rotation of the cutter body tothereby remove material from the rail and provide a desired rail profileor rail profile portion or region. In various embodiments, a vehicle isprovided including one or more milling cutters configured to mill adesired profile in a railway rail, true the rail, and provide acontinuous finish while traversing the rail at speeds greater that 1mph, such as greater than 3 mph, up to 15 mph, 1 to 15 mph, 5 to 15 mph,10 to 15 mph, or faster speeds. In certain embodiments, the millingcutter may be mounted on a vehicle and is movable about one or more axessuch that the milling cutter may be adjustably positioned proximate tothe rail in one or more orientations to restore the rail to a desiredprofile.

In one embodiment, one or more milling cutters provided on a railwayvehicle may be rotatable about a vertical axis or about an axis at anangle to the vertical. For example, a milling cutter comprising aplurality of cutting inserts secured about a periphery of a face of themilling cutter may be positioned proximate to a rail to engage andthereby mill and impart a desired profile or profile portion or regionto the rail. According to one embodiment, such a milling strategy may beconsidered a form of face milling, which the present inventors havediscovered allows for high feed rates by suitably distributing chipload. The use of face milling distinctly differs from milling strategiesknown for rail re-profiling, such as peripheral milling. Peripheralmilling may include a cutter mounted and rotated on a horizontal axis,and cutting inserts are spaced about the periphery of the milling cutterin an arrangement defining the profile to be cut. Railway vehiclesconducting peripheral milling are not capable of moving at the speedspossible with rail re-profiling methods and apparatuses describedherein. The ability to mill profiles into railway rail in situ at higherspeeds than conventional peripheral milling re-profiling techniques mayreduce the time during which the railway is out of service forre-profiling. In addition to lacking an ability to traverse the rail athigh speeds, peripheral milling also lacks an ability to adapt to curvedrail sections. Peripheral milling vehicles, which include single cuttersdefining the form to be cut, may produce deviations from a desired railprofile along curved rails, as well as produce an undesirable scallopedfinish on the railhead.

In certain embodiments according to the present disclosure, multipleface milling cutters may be mounted on a rail vehicle and areindividually positionable to contact the rail in different orientationsto re-profile the rail. The multiple milling cutters may be orientatedsuch that at least two of the milling cutters are positioned to milldifferent portions or regions of the desired rail profile on the rail.For example, in one embodiment, a first milling cutter may be positionedto mill a first facet on the rail, and a second milling cutter may bepositioned to mill a second facet on the rail. Both the first and secondfacets may be simultaneously milled on different regions of the rail asa vehicle on which the milling cutters are mounted traverses the rail.

In one embodiment according to the present disclosure, the millingcutters may be mounted on one or more dedicated rail vehicles. Themilling cutters may each be operably coupled to a dedicated or sharedmotor operable to rotate the milling cutters at a desired rate. In oneembodiment, two or more milling cutters may couple to a positioningmember or system configured to position the milling cutter proximate toa rail. The positioning member or system may comprise motors, gears,hydraulics, pumps, or the like. In various forms, the positioning memberor system may be manually operated, computer assisted, or automated. Forexample, in one embodiment, a positioning member or system is operablycoupled to a control system configured to control various operations ofthe milling cutter. In one embodiment, the control system comprises aguidance system. The guidance system may be programmed to scan ahead ofthe milling cutter, e.g., employing a laser or other detectionapparatus, to provide information to the guidance system regarding thecharacteristics of approaching segments of the rail. The guidance systemmay use the information to calculate an optimum depth of cut, width ofcut, or modification to a milling cutter position or orientation, orsupply of power. In various embodiments, the guidance system may controlor provide feedback to other system components to modulate a cuttingoperation, either directly or indirectly. For example, feedback from theguidance system may result in a modification to the position of thespindle head.

Referring to FIGS. 1A, 1B, and 2, in various embodiments according tothe present disclosure, a method and apparatus for profiling a railwayrail comprises rotating a milling cutter 10 about an axis “A” and in acontrolled orientation and position while contacting a railway rail 11.The milling cutter 10 may include a cutter body 12 that defines acentral diameter 14 and an outer circumference 16. The cutter body 12may include a cutter face 18 defining a plurality of cutting insertpositions 20 disposed about a periphery 22 of the cutter face 18. Eachof the plurality of cutting insert positions 20 may be configured toreceive a cutting member, e.g., a cutting insert 24. The cutting inserts24 may be positioned within the insert positions 20 and retained thereinwith a retaining assembly 26, e.g., a wedge, bolt, or other clampingassembly known in the art. The milling cutter 10 illustrated in FIG. 1Acomprises a plurality of cutting inserts 24, each positioned within anest 28. The cutting inserts 24 may be positioned to extend a distancefrom the cutter face 18 to engage a workpiece, e.g., a rail 11, at oneor more cutting edges 30 of the individual cutting insert 24. In variousembodiments, the central diameter 14 of the cutter body 12 may bedimensioned to mount to a spindle 32 for rotation about rotation axis“A”. The cutter body 12 further defines a plurality of holes 34structured to receive bolts to fix the rotation of the spindle 32 to thecutter body 12.

In operation, the milling cutter 10 may be rotated by the spindle 32while continuously traversing the rail 11 so that the rail 11 iscontinuously fed to the rotating cutting inserts 24 positioned about theperiphery of the cutter face 18, as generally depicted in FIG. 1B. Toproduce a desired profile or facet (i.e., a profile portion or region)on a region of the rail 11, the milling cutter 10 and the cuttinginserts 24 secured thereto may be orientated at a predetermined anglewith respect to the axis “X-X” of the rail 11. For example, in oneembodiment, the milling cutter 10 is positioned relative to the rail 11so that the cutting edges 30 of the cutting inserts 24 are positioned ina predetermined plane corresponding to at least a portion or region ofthe profile to be milled on the rail 11.

In various embodiments, a rail re-profiling apparatus and methodcomprises a rotating milling cutter 10 having a plurality of cuttinginserts 24 mounted around the periphery 22 of the cutter face 18.According to certain embodiments, the milling cutter 10 may traverse aworkpiece, e.g., a railway rail, at a speed of less than 1 mph up toabout 15 mph, at 5 to 15 mph, at 10 to 15 mph, or at faster speeds. Forexample, the milling cutter 10 may be rotated and pass along the rail 11such that the rail 11 is fed to the rotating milling cutter 10 at a feedrate corresponding to the speed of the vehicle on which the millingcutter 10 is mounted, to produce a desired rail profile.

To develop the disclosed milling apparatuses and methods forre-profiling surfaces on a railway rail while maintaining adequate railfinish and profile, various high feed milling cutter 10 and cuttinginsert 24 combinations where prepared and tested. In general, a highfeed milling cutter 10 was developed that utilizes insert lead angles tocreate a chip-thinning effect that allows the milling cutter 10 to runat higher than normal feed rates at relatively shallow depths of cut.According to various embodiments, the high feed milling cutter 10preferably comprises a medium pitch or a fine pitch milling cutter. FIG.1A is a perspective view of a generalized depiction of a milling cutter10 configurable as a high feed milling cutter according to variousnon-limiting embodiments. For example, the milling cutter 10 may bemounted to a rail car for high speed milling of rails 11. In thisconfiguration, the milling cutter body 12 has an 8-inch diameter andincludes 16 cutting insert positions 20 housing 16 separate cuttinginserts. FIG. 2 illustrates a nested cutting insert configuration andincludes a cutting insert 24 in a nest 28 adapted to receive the insert.The illustration at the top right of FIG. 2 provides a top view of thecutting insert 24 and a nest 28 within which the cutting insert 28 innested. The illustration at the top left of FIG. 2 provides a side viewof the nest 28 and cutting insert 24. The illustration at the bottomright of FIG. 2 provides an end view, e.g., a view of the portion of thenest and cutting insert 24 positioned about the circumference of thecutter body 12 when held within the cutter body. The insert 24 isdisposed at a 2° lead angle (measured between 44 a and 44 b) in thenest, and the insert 24 has an 11° degree relief (measured between 29a-29 b).

The effectiveness of the milling cutter 10 for high speed milling ofrailway rails has been demonstrated by rotating the milling cutter 10against a rotating rail steel wheel to simulate traversing a railwayrail. Specifically, the milling cutter 10 was mounted to a spindle 32extending from a 30 horsepower test machine. The milling cutter 10 wasrotated counter-clockwise against a 37-inch diameter wheel formed ofrail steel that was rotated clockwise at various rotational speeds tocorrespond to a specific mph. The parameters of this test are providedin FIG. 3. During the test, the width of cut was maintained betweenabout 0.38-0.62 inches at a depth of cut of about 0.010 inches. In Tests1-3, the rotational speed of the milling cutter was progressively rampedfrom an initial 700 RPM up to 1500 RPM, and the rotational speed of therail steel wheel was progressively ramped from a rotational speedcorresponding to 0.5 mph up to a speed corresponding to 1 mph. A fullcomplement of 16 inserts were mounted on the milling cutter and used inTests 2-5 listed in FIG. 3. Following the speed ramping tests, newinserts 24 were positioned in the cutter body 12 for Test 4 and Test 5listed in FIG. 3 in order to evaluate two sets of PVD-coated carbideinserts 24. The cutting insert grades used in the testing wereGreenleaf® grade G-935, a PVD-coated C5 cemented carbide grade, andGreenleaf® grade G-915, a PVD-coated C1 cemented carbide grade, both ofwhich grades are available from Greenleaf Corporation, Saegertown, Pa.USA.

FIG. 4 (left panel) is a top view of a cutting edge 30 of a cuttinginsert 24 showing typical edge wear observed in Test 5. FIG. 4 (rightpanel) is a side view of the cutting edge 30 depicted in the left panel.Wear land (36 a-36 b) measurements were taken from each insert 24 todetermine which test grade performed more favorably. The average wearland (36 a-36 b) for cutting inserts made from Greenleaf® grade G-935material used in Test 4 was 0.009 inches, with 2 of the 16 insertsshowing more than 0.019 inches of wear land (36 a-36 b). The averagewear land (36 a-36 b) for the cutting inserts made from Greenleaf® gradeG-915 material used in Test 5 was 0.013 inches, with 6 of the 16 insertsshowing more than 0.019 inches of wear land (36 a-36 b).

While the heavy feed rate used in the testing, ranging between 0.037 to0.047 inches per insert per revolution (which may be shortened herein to“inches per insert”), produced less than optimal part finish, the partfinish was within acceptable limits. Consequently, the results at 1 mphdemonstrated that an acceptable rail finish may be achieved at higherfeeds. The results also demonstrated that with the proper milling cutterand cutting insert configurations, higher feed rates may be achievedwith acceptable insert wear.

To further demonstrate that railway rails may be milled at high travelspeeds while maintaining required rail finish and profile, according tothe present disclosure, various milling cutter configurations weremounted to a test machine and used to mill an 11 foot segment of railwayrail held in a rotary fixture to facilitate indexing for milling variousfacet angles on the rail. The test machine was equipped with a 35horsepower horizontal machining center capable of a maximum linear feedrate of 400 inch per minute (IPM), or about 0.38 mph. In this test, twomilling cutter and cutting insert geometries were evaluated using a10-inch diameter cutter body configured to hold 32 cutting inserts.

A first milling cutter and insert configuration 100 evaluated is shownin FIGS. 5A-5C. In the first configuration 100, the milling cutter 110comprises a neutral radial and a positive axial rake configuration 100.Referring to the radial view FIG. 5A and the plan views FIGS. 5B and 5Cof configuration 100, the milling cutter 110 comprises a cutter body 112defining a central diameter 114 and an outer circumference 116 extendingoutward a diameter “D”. The central diameter 114 is positioned about arotation axis “A”, and the milling cutter 110 is dimensioned to mount toa spindle 132. The milling cutter 110 includes a plurality of holes 134configured to receive bolts to fix the cutter body 112 to the rotationof the spindle 132. Those having ordinary skill in the art willappreciate that cutter bodies may comprise various arrangements ofspindle fittings. For example, cutter bodies 112 may be designed withfittings including holes or slots configured for mounting to one or morespindle or spindle adaptor designs. As such, unless stated otherwise,the present disclosure is not limited by the particular spindle fittingarrangements in the illustrated embodiments.

The cutter body 112 extends to a cutter face 118 defining 32 cuttinginsert positions 120 about a periphery 122 of the cutter face 118. Thecutting inserts, e.g., 124 x, 124 y, are secured within the insertpositions 120. Each of the cutting inserts extends a distance from thecutter face 118 and defines a cutting edge 130 extending from the cutterface 118. The cutter body 112 is configured to be rotated about axis “A”in the rotational direction indicated by arrow “R”. The views shown inFIGS. 5A-5C illustrate geometries of the cutting inserts 124 x, 124 y.Cutting insert 124 y is shown at the six o'clock position in FIGS. 5Aand 5B illustrating a wiper flat portion 40 extending 0.140 inches to anangled portion 42 (see cutting insert detail in FIG. 7), providing a 2°angle (measured between 144 a and 144 b). Cutting insert 124 x is shownat the 3 o'clock position in FIGS. 5A and 5C illustrating a positiverake. It is to be appreciated that while cutting inserts 124 x, 124 yare referenced by different reference numbers, in various embodiments,inserts 124 x, 124 y, and the other insert mounted on the cutter body112 may share the same or similar geometries and orientations.

A second milling cutter and insert configuration 200 that was evaluatedis shown in FIGS. 6A-6C. In the second configuration 200, the millingcutter 210 comprises a double negative (axial and radial) rakeconfiguration 200. Referring to the radial view FIG. 6A and the planviews FIGS. 6B and 6C of the milling cutter 210, the milling cutter 200comprises a cutter body 212 defining a central diameter 214 and an outercircumference 216 extending to a diameter “D”. The central diameter 214is positioned about a rotation axis “A” and is dimensioned to mount to aspindle 232. The cutter body 212 defines a plurality of holes 234structured to receive bolts to fix the cutter body 212 to the rotationof the spindle 232. The cutter body 212 extends to a cutter face 218defining 32 insert positions 220 about a periphery 222 of the cutterface 218. The cutting inserts (e.g., 224 x, 224 y) are secured withinthe insert positions 220, extend a distance from the cutter face 218,and include cutting edges 230. The milling cutter 200 is rotated in therotational direction indicated by arrow “R”. The radial view or sideview of the milling cutter 210 illustrates geometries of the inserts 224x, 224 y. In the views provided in FIGS. 6A and 6B, cutting insert 224 yis shown at the six o'clock position illustrating a wiper flat portion40 extending 0.140 inches to an angled portion 42 (see cutting insertdetail in FIG. 7), providing a 2° angle (measured between 244 a and 244b). Cutting insert 224 x is shown at the 3 o'clock position in FIGS. 6Aand 6C illustrating a negative rake. It is to be appreciated that whileinserts 224 x, 224 y are referenced by different reference numbers, invarious embodiments, inserts 224 x, 224 y, as well as other cuttinginserts mounted on the cutter body 212, may share the same or similargeometries and orientations.

As indicated, FIG. 7 provides a semi-schematic detail view of thecutting inserts 124 y and 224 y depicted in FIGS. 5A-5C and 6A-6C,respectively, and further illustrates the geometry of the cuttinginserts and certain evaluated parameters. The cutting insert 124 y, 224y is depicted in FIG. 7 engaging a railway rail 11, and the insertincludes a wiper flat portion 40 transitioning to an angled portion 42.The programmed feed rate 70, actual chip load (between 72 a and 72 b),and maximum depth of cut (between 46 a and 46 b) indicated in FIG. 7generally correspond to the test parameters, which are further describedbelow.

In addition to evaluating milling cutter and cutting insert geometries,relative orientations between a milling cutter and a railway rail alsowere investigated. FIG. 8 illustrates a side-by-side comparisondepicting “conventional” (up) milling 300 and “climb” (down) milling400. The lower portion of the figure depicts milling cutters 310, 410,which may be applicable to any of the milling cutters described herein.Both milling cutters 310, 410 are positioned proximate to a rail 11. Thecutter faces 318, 418 of the cutter bodies 312,412 retain a plurality ofcutting inserts 324, 424 comprising cutting edges 330, 430 positioned tomill the rail 11 when the cutter 310, 410 rotates in the direction ofarrows “R” about rotation axis “A”. The rail 11 may define an axis “X”.According to certain embodiments, the rail 11 may be fed to the cuttinginserts 324, 424 with the milling cutter 310, 410 traversing the rail,as indicated by arrow 52. In the upper portion of FIG. 8, the millingcutters 310, 410 are illustrated in an axial perspective from thespindle at the back of the milling cutter body 312, 412. In a“conventional” milling orientation 300, the chip thickness starts at ornear zero and increases to a maximum to form the width of cut (measuredbetween 48 a and 48 b). In a “climb” milling orientation 400, eachcutting edge engages the material at a definite point and the width ofcut (between 48 a and 48 b) starts at a maximum and decreases throughoutthe cut. In both orientations depicted in FIG. 8, the axis “A” of themilling cutter 310, 410 is offset from axis “X”, as generallyillustrated in FIG. 8. In various embodiments, however, the axis “A” ofthe milling cutter 310, 410 may be at least partially centered on axis“X” when the milling cutter 310, 410 is milling the rail 11.

FIG. 9 depicts a milling cutter 510 coupled to a spindle 532 andperforming work on a rail 11 in an offset orientation 500. Inparticular, milling cutter 510 comprises a cutter body 512 configured tohouse a plurality of cutting inserts 524 positioned about a periphery522 of a cutter face 518 of the milling cutter 510. As introduced above,the milling cutter 510 may be positioned in either a conventionalmilling orientation or a climb milling orientation. As shown in FIGS.8-9, the rotation axis “A” may be partially offset from axis “X”, e.g.,and the rotation axis “A” may be centered along the facet or width ofcut as shown in FIG. 10. FIG. 10 illustrates a milling cutter 610coupled to a spindle 632 and performing work on a rail 11 in a centeredorientation 600. The milling cutter 610 comprises a cutter body 612configured to house a plurality of cutting inserts 624 positioned abouta periphery 622 of a cutter face 618 of the milling cutter 610.

As described above, to further demonstrate that rails 11 may be milledat high speeds while maintaining adequate rail finish and profileaccording to the present disclosure, milling cutters 110, 210, 310, 410,510, 610 comprising the above cutter body/cutting insert configurations100, 200 and orientations 300, 400, 500, 600 were mounted to a testmachine providing a maximum linear feed rate of 400 IPM (inches perminute) to mill an eleven-foot long railway rail 11 held in a rotaryfixture 60 (as shown in FIG. 10). The rotary fixture facilitatesindexing the rail 11 for milling various facet angles on the rail 11.During the testing, the negative rake configuration 200 was observed toprovide a better part finish at higher feed rates than the positive rakeconfiguration 100. For example, compared to the positive rakeconfiguration 100, the finish produced by the negative rakeconfiguration 200 appeared less wavy at the higher feed rates. Notably,the negative rake configuration 200 cutting inserts 24 also offeradditional cutting edges. Climb milling 400 with the milling cutter 410,510 in an offset position 500 approximately 4 inches off center axis “A”was also found to provide a quieter cut with a better surface finish.FIG. 11 provides parameters of the testing, in which 32 test runs(G001-G0032) were conducted to evaluate the double positive millingcutter configuration 100 oriented on-center 600.

Referring to FIG. 12A, to address the various rail facets that may bemilled in a rail to together provide a desired railhead profile, testingwas conducted in which the milling cutter was positioned at variouscutter tip angles 56 a-56 b off the horizontal “B” through approximately45°. FIG. 12B illustrates nine examples of cutter tip angles off thehorizontal “B” on both sides of the rail for profile or facet regions 82a, 82 b on a rail 11. The nine set of facets (18 total facets) weremilled on the rail 11 using configuration 100 or 200 to provide adesired rail profile or contour. During testing, the width of cut(measured between 48 a and 48 b) was approximately 0.12-1.12 inches, andthe depth of cut was maintained between 0.005 and 0.010 inches (see,e.g., FIG. 7). Only four inserts where mounted on the cutter body toperform the test. Consequently, the work performed by each cuttinginsert was estimated to equate to about 3.03 mph at a full load of 32inserts. Various features of the milling cutter 710 illustrated in FIG.12A may be similar to the features of the milling cutter 410 illustratedin FIG. 8. For example, milling cutter 710 was positioned in an offsetorientation 700. Accordingly, like features are identified by numberscorresponding to features of milling cutter 410 and, for purposes ofbrevity, are not further described.

As stated above, the maximum linear IPM feed for the test machine usedin the test was 400 IPM. Accordingly, to further push linear feedevaluation, in mph, various test passes where run using only 1 or 2cutting inserts. The parameters for these tests are provided in FIG.13A. Both positive (Tests 1-7) and negative (Tests 8-10) milling cutterconfigurations 100, 200 were tested. A climb milling orientation 400combined with an offset cutter-rail orientation 700 of 4 inches was usedin all the tests. Width of cut was approximately 0.12-1.12, and theinsert grade was Greenleaf® grade GA-5125 material, a CVD-coated C6grade, available from Greenleaf Corporation, Saegertown, Pa. USA. TheIPM feed was varied between 242.0 IPM and 400.4 IPM. The estimated mphfeed with a full insert load of 32 inserts is between 4.83 mph and 12.00mph. For example, for Tests 6 and 10, the programmed feed was run at0.360 feed per insert (see, e.g., FIG. 7) at 1,100 RPM, reaching 396.0IPM of linear feed with one insert. With a full load of 32 cuttinginserts run at an equivalent inch per insert feed rate, the estimatedmph feed is about 12 mph. FIG. 13B is a photographic depiction ofcutting inserts used in tests G008, G001, and G002. The insert tops orrake faces showed no damage and only flank wear was visible. The wearland (between 36 a and 36 b) for the G002 insert was measured to about0.025 inches. Notably, increased wear was observed at the 2° wiper flattransition (generally at line T-T). It is believed that addition of aradius to the cutting insert may reduce the observed increase in wear inthis region.

FIG. 14A provides test parameters used to evaluate two coated cementedcarbide cutting insert grades: Greenleaf® grade GA-5125 (Test 1) andGreenleaf® grade G-955 (Test 2), both of which are available fromGreenleaf Corporation, Saegertown, Pa., USA. For Tests 1 and 2, themilling cutter 210 included only a single cutting insert 24 in anegative rake configuration 200. A climb milling orientation 400 wasused in both tests, and the milling cutter was oriented at a cutter-railoffset 700 of 4 inches. The programmed feed per insert at 825 RPM was0.360, reaching 297 IPM linear feed with the single insert. Theequivalent mph feed with a full insert load of 32 cutting inserts isestimated to be about 9.00 mph. Width of cut was approximately 0.12-0.5inches 14B. FIG. depicts a rail 511 re-profiled in the test, evidencingacceptable part finish.

To further evaluate insert grades at an increased width of cut,additional tests were performed using cutter configuration 200 and threecoated cemented carbide insert grades: Greenleaf® grade GA-5125,Greenleaf® grade G-935, and Greenleaf® grade G-955, all of which areavailable from Greenleaf Corporation, Saegertown, Pa., USA. Theparameters for this test are provided in FIG. 15. Cutting insertscomposed of each grade were run in the same milling cutter for the sametime for comparison purposes. The depth of cut was 0.060 inches and thewidth of cut was maintained at approximately 2.50 inches. FIG. 16 is aphotographic depiction of the cutting inserts of each grade showing themost wear from each of the four tests. The cutting inserts from Test 1exhibited the most wear and indicated that for certain cutting inserts,as the width of cut increases, a corresponding decrease in insert lifemay be observed. Thus, in various embodiments, a plurality of millingcutters may be positioned such that one or more of the milling cuttersre-profiles a railway rail along a small facet or width of cut.Accordingly, as described in more detail below, a milling cutterapparatus according to the present disclosure may comprise a railvehicle having mounted thereto a plurality of milling cutters configuredto mill a plurality of facets to together define a desired rail profile.Comparing the cutting inserts from Test 1 with the cutting inserts fromTests 2-3 also shows that, as cutting speeds increase, a correspondingdecrease in cutting insert life may be observed. Thus, in variousembodiments, the plurality of milling cutters may be positioned suchthat one or more of the milling cutters are positioned to re-profile arail with a narrow facet and at a reduced RPM.

Referring to FIGS. 17A-17C, which provide an axial view FIG. 17A and aradial view FIG. 17B (a portion of which is magnified in the viewprovided in FIG. 17C of a milling cutter 810, the milling cutter 810comprises a cutter body 812 defining a central diameter 814 and an outercircumference 816 defined by diameter “D”. The central diameter 814 ispositioned about a rotation axis “A” and is dimensioned to mount to aspindle 832. The cutter body 812 defines a plurality of holes 834configured to receive bolts to fix the cutter body 812 to the rotationof the spindle 832. The cutter body 812 extends to a cutter face 818defining 32 insert positions 820 about a periphery 822 of the cutterface 818. The cutting inserts, e.g., 824 x, 824 y, are secured withinthe insert positions 820. The cutting inserts 824 x, 824 y extend adistance from the cutter face 818 to define cutting edges 830 extendingtherefrom, and the milling cutter 810 is configured to be rotated in therotational direction indicated by arrow “R”. The radial view or sideview of the milling cutter 810 illustrates geometries of the inserts 824x, 824 y. In the views provided in FIGS. 17A-17C, cutting insert 824 yis shown at the six o'clock position illustrating a substantially linearportion 878 of the insert 824 y presented at the cutter face 818. Angle844 a-844 b comprises about a 0° angle. Depth of cut is illustratedbetween 846 a-846 b. Cutting insert 824 x is shown at the 3 o'clockposition in FIGS. 17A and 17B illustrating a negative rake. It is to beappreciated that while inserts 824 x, 824 y are referenced by differentreference numbers, in various embodiments, cutting inserts 824 x, 824 y,as well as other cutting inserts mounted on cutter body 812, may sharethe same or similar geometries and orientations.

The milling cutter illustrated in FIGS. 17A-17C also comprises a bumperplate 880 positioned at the cutter face. In various embodiments, abumper plate 880 may be positioned adjacent to one or more cuttinginserts, e.g., 824 x, 824 y, between an inner circumference of themilling body and the periphery 822 of the cutter face 818, to protectthe cutter body and the inserts from wear and breakage due to excessivedepth of cut. The bumper plate 880 may also provide a hard stop to limitthe depth of cut from exceeding a maximum value. For example, in oneembodiment, a differential in axial extension of the bumper plate 880and the cutting insert 824 ax, 824 y may be defined between 882 a-882 b.This distance may be greater than the desired depth of cut 846 a-846 b.It is to be appreciated that any of the milling cutters disclosed hereinmay comprise a bumper plate. Additionally, it is contemplated that abumper plate may comprise a modular component that may be added whenneeded and then removed after use. In certain embodiments, multiplebumper plates may be provided for a particular milling cutter. Bumperplates may comprise various thicknesses or may be configured to beadjustable via shims, for example. Bumper plates may also comprise ringsor discs extending about a circumference of the cutter face 818. Bumperplates may comprise other shapes and configurations such as segmentedplates or segmented rings, for example. In various embodiments, thebumper plate comprises a ring including a rigid material to protect thecutter body. In certain embodiments, the bumper plate comprises a rigidmetallic material or a rigid polymer or ceramic.

Cutting insert wear is an important aspect that must be considered in arailway rail re-profiling method. When cutting inserts wear beyond acertain level, they must be indexed or replaced. In some instances,indexing or replacement may be a time-consuming process, and may furtherincrease the time that a railway segment is out of service. To furtherevaluate insert wear, additional tests were performed using the millingcutter configuration illustrated in FIGS. 17A-17C. In addition toproviding the configuration described above with respect to FIGS.17A-17C, the inserts 824 x, 824 y received an edge preparationcomprising a 0.015-0.020 inch land and a 0.002-0.003 inch hone. The testincluded mounting the milling cutter to a test carriage to re-profile alength of railway rail in situ. FIG. 18A provides the parameters usedfor the testing. FIG. 18B depicts a portion of the test carriage 884.The test carriage 884 comprised two milling cutters 810 a, 810 b mountedto spindle 832 a, 832 b, respectively. The cutter faces 818 a, 818 b arevisible. The milling cutters 810 a, 810 b were separately angled anddisposed in an offset orientation with respect to the rail 11 to millsegments of a profile on the rail.

FIGS. 19A-19C depict the cutting inserts used in Tests 4-8 referenced inFIG. 18A. FIG. 19A includes cutting edges (shown toward the top of thepage) for 16 cutting inserts, representing 8 cutting inserts for eachmilling cutter (although the milling cutter was equipped to hold 32cutting inserts). As can be seen from FIGS. 19A-19C, the same cuttinginsert cutting edges could be run much farther until indexing wasnecessary. The finish of the rails following re-profiling using theapparatus and method as described herein was determined to beacceptable. FIG. 19B depicts a magnified view of cutting insert 924. Theindicated portion of the cutting edge 930 is further magnified in FIG.19C, which shows the top 925 of the cutting insert 924. The edge prep isindicated between 927 a-927 b. The wear land (between 936 a-936 b) wasapproximately 0.010-0.015 inches. As understood to those having ordinaryskill, a wear land is a flattened worn area on a cutting insert cuttingedge that forms due to abrasive wear from contacting a workpiece (suchas, e.g., a railway rail). It is believed that as wear lands increase,the milled surface finish of the rail may deteriorate, and cuttingpressures and power consumption may also increase. Due to the uniquenature of the disclosed apparatuses and methods, wear lands may be ableto increase to 0.04 inches and beyond before adverse affects require acutting insert to be indexed or replaced.

Referring to FIGS. 20A and 20B, according to various embodiments, amilling cutter 910 comprises a bumper ring 990 positioned about thecutter face 918. The milling cutter 910 may comprise features similar toany of the milling cutters disclosed herein. Accordingly, similarfeatures are identified by similar reference numbers and, for the sakeof brevity, will not be repeated. The bumper ring 990 comprises a ringextending about a circumference of the milling cutter 910, outward ofthe periphery of the cutter face 922 housing the cutting inserts. Forexample, a radial distance between a cutting insert 924 and the rotationaxis “A” is shorter than a radial distance between the bumper ring 990and the rotation axis “A”. In addition to a bumper ring 990, the millingcutter 910 also comprises a bumper plate 980 positioned at the cutterface. In various embodiments, a bumper plate 980 may be positionedadjacent to one or more cutting inserts, e.g., cutting inserts 924 x,924 y, between an inner circumference of the milling body and theperiphery 922 of the cutter face 918, to protect the cutter body 912.The bumper ring 990 may provide a hard stop to limit the depth of cutfrom exceeding a maximum value, such as when traversing transitions,gaps between rails, or mushroomed joints. In one embodiment, adifferential in axial extension of the bumper ring 990 and the cuttinginsert 924 ax, 924 y may be defined between 992 a and 992 b. Thisdistance may be greater than the desired depth of cut and, when themilling cutter 910 is also equipped with a bumper 980, the axialextension of the insert 924 x, 924 y may be greater than both the bumperplate 980 and the bumper ring 990. It is to be appreciated that any ofthe milling cutters disclosed herein may comprise a bumper plate 980and/or a bumper ring 990. In some embodiments, the bumper plate 980and/or the bumper ring 990 may be modular. For example, the bumper ring990 may be removable or customizable. In one embodiment, shims may beplaced between the bumper ring 990 and the cutter body 912 at position994 to increase the axial extension of the bumper ring 990. It iscontemplated that the bumper ring 990 may comprise a modular component.The modular component may be added when needed or removed when notneeded. In certain embodiments, multiple bumper rings 990 may beprovided to suit a desired milling cutter. Bumper rings 990 may comprisevarious thicknesses or may be configured to be adjustable via shims, forexample. Bumper rings 990 may also comprise rings, plates, or discsextending about a circumference of the cutter face 918. Bumper rings mayalso comprise segmented rings, plates, or discs. In various embodiments,the bumper ring comprises a ring comprising a rigid material to protectthe cutter body. In one embodiment, the bumper plate comprises a rigidmetallic material or a rigid polymer or ceramic.

FIG. 21 illustrates a first milling cutter 1010 and a second millingcutter 1110, each comprising a cutter body 1012, 1112 having a pluralityof cutting inserts 1024, 1124 disposed along the periphery of a cutterface 1018, 1118. The cutting inserts define cutting edges 1030, 1130configured to engage the rail 11 to form a rail profile. Both millingcutters 1010, 1110 are positioned in an offset orientation such that therotation axis “A” is offset from the axis “X” of the rail and the work.In operation, the first and second milling cutters 1010, 1110 rotateabout their respective rotation axes “A” and may traverse the rail 11 atspeeds of 1 mph or more. The rotation of the milling cutters 1010, 1110may pass the cutting edges 1030, 1130 of the cutting inserts 1024, 1124over the rail 11 such that each sequentially engages the rail to removea portion of rail material. As shown, multiple milling cutters 1010,1110 may be positioned about the rail 11. One or more of the millingcutters 1010, 1110 may be positioned in different angular orientationswith respect to the rail 11. Thus, in certain embodiments, a pluralityof milling cutters may be positioned in differing orientations about therail 11 to mill a plurality of facets (i.e., profile regions orsegments) along the rail and thereby provide the desired rail profile.In FIG. 21, the first milling cutter 1010 forms a facet along the railat a position generally indicated by arrow 50, while the second millingcutter 1110 forms a facet along the rail 11 at a position generallyindicated by arrow 51. In various embodiments, multiple milling cutters1010, 1110 may be positioned proximate to multiple tracks and may bemounted on the same or multiple rail vehicles. For example, in oneembodiment, one or more large diameter milling cutters are mounted to afirst rail vehicle and one or more smaller diameter milling cutters aremounted to the first rail vehicle in a different position or are mountedto a second rail vehicle. The large diameter milling cutters may performthe majority of the work on open rail, while the small diameter millingcutters may be engaged for tighter working conditions, such as neartransitions or at grade crossings.

In various embodiments, a method of profiling a rail comprisespositioning a pair of milling cutters 1024, 1124 proximate to the rail11, traversing the rail 11, engaging the rail 11 with cutting edges1030, 1130, and milling the rail 11. For example, a first milling cutter1024 may be positioned at a first angle and a second milling cutter 1124may be positioned at a second angle relative to the rail. In oneembodiment, the first milling cutter 1024 is positioned proximate to oneside of the rail at a first angle to the rail, the second milling cutter1124 is positioned proximate to the other side of the rail at a secondangle to the rail, and the first and second angles are substantially thesame (e.g., a-a, b-b in FIG. 12B). Accordingly, the pair of millingcutters 1024, 1124 may be positioned to mill a set of matched facetsalong both sides of the rail. In one such embodiment, multiple pairs ofmilling cutters may be positioned along the rail 11 such that each pairmills a set of matched facets while traversing the rail 11. In oneembodiment, the pairs of milling cutters are positioned to progressivelyor sequentially mill the rail from a lower portion of the profile to ahigher portion of the profile. For example, with reference to FIG. 12B,a first pair of milling cutters may be positioned to mill matched facetsa-a, b-b, and a second pair of milling cutters may be positioned to millmatched facets c-c, b-b. In one embodiment, as the rail vehicle movesalong the rail 11, a first pair of milling cutters engages the rail andmills a first matched set of facets, a second pair of milling cuttersengages the rail 11 and mills a second set of matched facets, and athird pair of milling cutters engage the rail 11 and mills a third setof matched facets. The first set of matched facets may be located belowthe second set of matched facets, and the second set of matched facetsmay be positioned below the third set of matched facets. In one suchembodiment, the first set of matched facets is milled before the secondset of matched facets (as the re-profiling vehicle traverses the rail),and the second set of matched facets is milled before the third set ofmatched facets. Accordingly, in one embodiment, a method of re-profilinga railway rail 11 comprises positioning a plurality of milling cuttersproximate to the rail 11 such that the plurality of milling cutterssequentially mills sets of matched facets from a lower portion of therail to a higher portion of the rail. Because the width of the railbeing re-profiled will generally be much less than the diameters of themilling cutters, pairs of milling cutters will typically be spaced aparton one or more re-profiling vehicles along a length of rail. Forexample, milling cutters may be staggered along one or both sides of arail. Also, it will be understood that unpaired milling cutters (i.e.milling cutters not part of a set) may be employed in the methods andapparatuses according to the present disclosure. Accordingly, in certainembodiments, one or more unpaired milling cutters may be mounted on acarriage or other rail vehicle to mill portions or segments of a profileinto a rail in situ, and such carriage or vehicle may or may not alsoinclude paired sets of milling cutters mounted thereon.

In various embodiments, milling cutters used according to the presentdisclosure may include cutting inserts comprising uncoated cementedcarbide grades, such as, for example, C6 carbide, or coated cementedcarbide grades, such as, for example, coated C6 carbide. Coated carbidegrades may be selected from, e.g., PVD or CVD coated carbides. Invarious alternate embodiments, milling cutters used according to thepresent disclosure may include cutting inserts comprising uncoatedceramic grades (for example, Greenleaf® WG-300 material) or coatedceramic grades (for example, Greenleaf® WG-600 material).

According to various embodiments, a face milling cutter including a setof 8 cutting inserts mounted thereon may be rotated on a milling cutterat 300 RPM and advance along a railway rail at 1 mph for at least 18,000feet (ft), 27,000 ft, or farther before requiring indexing orreplacement of one or more of the cutting inserts. In a furtherembodiment, because wear is generally proportional to work performed bythe cutting tool, a similar milling cutter configuration comprising aload of 32 cutting inserts may run at 300 RPM and advance along arailway rail at 4 mph for a distance of 108,000 ft (20.45 miles) beforerequiring indexing or replacement of one or more of the cutting inserts.

As described above, another factor in regard to cutting insert life isdepth of cut. As disclosed herein, maintaining depth of cut to around0.005-0.010 inches may beneficially increase cutting insert life as wellas adequately re-profile railway rails without significant removal ofmaterial that may otherwise unacceptable shorten the operational life ofthe rail. However, in various embodiments, it may be desirable ornecessary to increase depth of cut beyond 0.010 inches, for example to0.040 inches or more. In certain embodiments, the method may involvescontrolling the depth of cut of the cutting inserts to a depth no morethan 0.040 inches, no more than about 0.010 inches, or between 0.005inches and 0.010 inches.

Accordingly, unless stated otherwise, the present disclosure is notlimited to a 0.0010 inch depth of cut or any other depth of cutdescribed herein.

Also, as described above, one factor to consider in regard to cuttinginsert life is facet width or width of cut. For example, maintainingfacet width on the rail to a minimum, such as 0.31 inches or less insome instances, may result in enhanced cutting insert life. Also, forexample, in certain embodiments the width of cut may be limited to about0.625 inches or less when milling a segment or portion of a profile on arail.

According to various embodiments, the thickness of cutting inserts maybeneficially increase the operational life of the cutting inserts. Forexample, because the wear land will increase dramatically as the cuttingedge in one area progresses down the length of the cutting insert,increasing a thickness of the cutting inserts may allow furtherutilization all cutting edges.

In various embodiments, a milling cutter may be configured to enhancecutting insert life in railway rail re-profiling applications. Forexample, whereas a cutting insert comprising an insert edge having alinear, e.g., wiper, portion extending a first distance to an angledportion may lose operational life once the linear portion has worn away,a cutting insert comprising a more sweeping radii or an insert edgehaving a linear portion extending a second distance, greater than thefirst, may result in additional insert life. That is, when the linearportion is worn in one area of the cutting insert edge, the actualcutting edge may move to a fresh area of the Insert. In one embodiment,dimensions of a cutting insert may comprise a width of 0.375 inches, athickness of 0.25 inches, and length of 0.75 inches. Where the cuttingedged is located along the length of the insert, increasing the lengthof the insert from 0.75 inches to 1.125 inches or more may provideadditional cutting insert life. For example, the cutting edge maycomprise an actual cutting edge. The actual cutting edge mayprogressively move along the edge as it wears. In one embodiment, acutting edge of one or more of the cutting inserts may comprise anactual cutting edge. The actual cutting edge may, in some instances, maytransition along the cutting edge from a first position to a secondposition when the first position wears, thereby increasing cuttinginsert life.

Those having ordinary skill in the art, on considering the presentdescription of certain embodiments, will appreciate that the particulardesired dimensions of a cutting insert may depend on the desiredapplication, such as the shape, form, location, or environment of arailway rail. Therefore, unless stated otherwise, the above dimensionsare merely examples of cutting insert dimensions.

As described above, in various embodiments, the milling cutter may bepositioned in an offset configuration with respect to the rail. Forexample, 3 to 4.5 inches may separate the rotation axis of the millingcutter from the work performed along a rail. In various non-limitingembodiments, and using a 10 inch milling cutter as a scalable reference,milling cutters may be positioned at an offset of between 3.5 inches and4.0 inches, or may be positioned at an offset of about 3.75 inches. Incertain embodiments, the milling cutter may be positioned in an offsetorientation comprising a distance between 35% and 40% of the millingcutter diameter. As also described above, in various embodiments, aplurality of milling cutters may be positioned to simultaneously and/orsequentially mill a rail profile. In one embodiment, the milling cuttersmay define cutting angles between 0° and about 55° about the railprofile.

According to various embodiments, cutting inserts may be supplied withvarious edge preparations. For example, edge preparations may include0.002-0.003 inch hone only and a 0.015-0.020 inch×20° negative land witha 0.002-0.003 inch hone. In certain embodiments, reducing the rotationalspeed of the milling cutter may significantly increase insert life. Inone embodiment, the rotational speed of the milling cutter may bereduced and the feed rate or speed of traverse may be increased toincrease cutting insert life.

It will be appreciated that while the present disclosure may provideexemplary milling cutter bodies defining 32 cutting insert positions, itis contemplated that milling cutters equipped to accept more than orless than 32 cutting inserts may be used with the methods andapparatuses of the present disclosure. For example, the number ofcutting inserts that may be mounted on a face milling cutter isgenerally determined by the circumference of the peripheral portion ofthe cutter body defining the insert positions and/or the size of thecutting inserts. In various non-limiting embodiments, the diameter ofthe milling cutter may be between 8 inches and 16 inches, or between 10inches and 12 inches. In some embodiments, milling cutters comprisingdiameters less than 10 inches, such as 4 inches, may be used alone or incombination with other milling cutters comprising diameters that may beless than, greater than, or equal to the milling cutter comprising lessthan a 10-inch diameter. It is contemplated that reduced diametermilling cutter configurations may be beneficial for milling of difficultto reach segments of rail profile, such as rail at transitions,platforms, or grade crossings. It is also contemplated that millingcutters comprising diameters greater than 10 inches may be used alone orin combination with other milling cutters comprising diameters lessthan, greater than, or equal to the milling cutter comprising greaterthan a 10 inch diameter. It is contemplated that increased diametermilling cutters may be used to increase speed or operational life ofvarious sets of cutting inserts. For example, longer insert life spansmay increase productivity and shorten rail outage periods due tore-profiling because maintenance personnel will not be required tointerrupt the re-profiling process to index or replace cutting insertsas frequently.

In the present description of embodiments, other than in the operatingexamples or where otherwise indicated, all numbers expressing quantitiesor characteristics of elements, products, processing or test conditionsor parameters, and the like are to be understood as being modified inall instances by the term “about”. Accordingly, unless indicated to thecontrary, any numerical parameters set forth in the followingdescription are approximations that may vary depending upon the desiredproperties one seeks to obtain in the apparatuses and methods accordingto the present disclosure. At the very least, and not as an attempt tolimit the application of the doctrine of equivalents to the scope of theclaims, each numerical parameter should at least be construed in lightof the number of reported significant digits and by applying ordinaryrounding techniques.

This disclosure describes various elements, features, aspects, andadvantages of various embodiments of rail re-profiling apparatus andmethods, systems, and methods thereof. It is to be understood thatcertain descriptions of the various embodiments have been simplified toillustrate only those elements, features and aspects that are relevantto a more clear understanding of the disclosed embodiments, whileeliminating, for purposes of brevity or clarity, other elements,features and aspects. Any references to “various embodiments,” “certainembodiments,” “some embodiments,” “one embodiment,” or “an embodiment”generally means that a particular element, feature, and/or aspectdescribed in the embodiment is included in at least one embodiment. Thephrases “in various embodiments,” “in certain embodiments,” “in someembodiments,” “in one embodiment,” or “in an embodiment” may not referto the same embodiment. Furthermore, the phrases “in one suchembodiment” or “in certain such embodiments,” while generally referringto and elaborating upon a preceding embodiment, is not intended tosuggest that the elements, features, and aspects of the embodimentintroduced by the phrase are limited to the preceding embodiment;rather, the phrase is provided to assist the reader in understanding thevarious elements, features, and aspects disclosed herein and it is to beunderstood that those having ordinary skill in the art will recognizethat such elements, features, and aspects presented in the introducedembodiment may be applied in combination with other various combinationsand sub-combinations of the elements, features, and aspects presented inthe disclosed embodiments.

Although the foregoing description has necessarily presented only alimited number of embodiments, those of ordinary skill in the relevantare will appreciate that various changes in the apparatuses and methodsand other details of the examples that have been described andillustrated herein may be made by those skilled in the art, and all suchmodifications will remain within the principle and scope of the presentdisclosure as expressed herein and in the appended claims. For example,although the present disclosure has necessarily only presented a limitednumber of embodiments of rail re-profiling apparatuses and methods, itwill be understood that the present disclosure and associated claims arenot so limited. Those having ordinary skill will readily identifyadditional rail re-profiling apparatuses and methods and may design andbuild and use additional rail re-profiling apparatuses and methods alongthe lines and within the spirit of the necessarily limited number ofembodiments discussed herein. It is understood, therefore, that thepresent invention is not limited to the particular embodiments ormethods disclosed or incorporated herein, but is intended to covermodifications that are within the principle and scope of the invention,as defined by the claims. It will also be appreciated by those skilledin the art that changes could be made to the embodiments and methodsdiscussed herein without departing from the broad inventive conceptthereof.

What is claimed is:
 1. A method of milling at least a portion of a profile on a railway rail in situ, the method comprising: rotating a milling cutter about a rotation axis, the milling cutter comprising a cutter body including a cutter face, and a plurality of cutting inserts mounted around a periphery of the cutter face, each of the plurality of cutting inserts comprising a cutting edge, each cutting edge including two ends, wherein as the milling cutter rotates about the rotation axis the ends of the cutting edges define a circular ring comprising an inner radius, defined by inner ends of the cutting edges, and an outer radius, defined by outer ends of the cutting edges; milling a facet of the profile on the railway rail in situ with the cutting edges as the milling cutter rotates about the rotation axis while controlling the depth of cut of the cutting inserts, wherein a distance between the rotation axis and a closer edge of the facet is less than a distance from the rotation axis to the inner radius of the circular ring, and wherein the rotation axis is offset from the facet being milled on the railway rail by the cutting inserts; traversing the railway rail in situ with the milling cutter while milling the railway rail; and controlling the speed of traverse of the milling cutter along the railway rail.
 2. The method of claim 1, comprising controlling the speed of traverse of the milling cutter along the railway rail to speeds up to 15 mph.
 3. The method of claim 1, comprising controlling the speed of traverse of the milling cutter along the railway rail to speeds greater than 1 mph.
 4. The method of claim 1, comprising controlling the speed of traverse of the milling cutter along the railway rail to speeds greater than 3 mph.
 5. The method of claim 1, comprising controlling the speed of traverse of the milling cutter along the railway rail to speeds between 1 mph and 15 mph.
 6. The method of claim 1, comprising controlling the depth of cut of the cutting inserts to a depth no more than 0.040 inches.
 7. The method of claim 1, comprising controlling the depth of cut of the cutting inserts to a depth no more than 0.010 inches.
 8. The method of claim 1, comprising controlling the depth of cut of the cutting inserts to a depth between 0.005 inches and 0.010 inches.
 9. The method of claim 1, wherein milling a facet of the profile on the railway rail comprises milling the railway rail using a conventional milling orientation.
 10. The method of claim 1, wherein milling a facet of the profile on the railway rail comprises milling the railway rail using a climb milling orientation.
 11. The method of claim 1, wherein the milling cutter mills a width of cut of 0.625 inches or less on the railway rail in situ.
 12. The method of claim 1, wherein the milling cutter further comprises one of a bumper ring and a bumper plate.
 13. The method of claim 1, wherein the cutting edge of each cutting insert comprises a cutting edge portion that contacts the railway rail during the milling, and wherein the cutting edge portion that contacts the railway rail during the milling progressively moves along the respective cutting edge as the cutting edge wears.
 14. The method of claim 1, wherein the cutting edge of at least one of the cutting inserts is substantially linear.
 15. The method of claim 1, wherein the cutting inserts comprise one of uncoated C6 grade cemented carbide and coated C6 grade cemented carbide.
 16. The method of claim 1, wherein the rotation axis of the milling cutter is offset from the facet being milled on the railway rail by a distance between 35% and 40% of the diameter of the milling cutter.
 17. The method of claim 1, wherein the milling cutter comprises a diameter between 8 inches and 16 inches.
 18. The method of claim 1, wherein the milling cutter mills a width of cut of 0.12 to 1.12 inches on the railway rail in situ.
 19. The method of claim 1, wherein the milling cutter comprises a diameter between 4 inches and 16 inches.
 20. The method of claim 1, wherein a portion of the cutting edge of one or more of the cutting inserts is in contact with the railway rail at any one time, wherein the portion of the cutting edge in contact with the railway rail moves along the respective cutting edge as the respective cutting edge wears.
 21. The method of claim 1, wherein the milling cutter is mounted to a carriage that moves along the railway rail in situ.
 22. The method of claim 1, wherein the rotation axis of the milling cutter is offset from the facet being milled on the railway rail by a distance of 3 to 4.5 inches.
 23. The method of claim 1, comprising controlling the speed of traverse of the milling cutter along the railway rail to speeds greater than 15 mph.
 24. The method of claim 1, wherein the rotation axis of the milling cutter is offset from the facet being milled on the railway rail by 3 inches to 4.5 inches.
 25. The railway rail milling apparatus of claim 1, wherein the cutting edge of each cutting insert has a length greater than a width of the facet to be milled on the railway rail.
 26. The railway rail milling apparatus of claim 1, wherein the cutting edge of each of the cutting inserts is disposed in a plane that is parallel to a plane of rotation of the milling cutter.
 27. A method of milling at least a portion of a profile on a railway rail in situ, the method comprising: rotating a milling cutter about a rotation axis, the milling cutter comprising a cutter body having a diameter between 4 inches and 16 inches and including a cutter face, and a plurality of cutting inserts mounted around a periphery of the cutter face, each of the plurality of cutting inserts comprising a cutting edge, each cutting edge including two ends, wherein as the milling cutter rotates about the rotation axis the ends of the cutting edges define a circular ring comprising an inner radius, defined by inner ends of the cutting edges, and an outer radius, defined by outer ends of the cutting edges; milling a facet of the profile on the railway rail in situ with the cutting edges as the milling cutter rotates about the rotation axis while controlling the depth of cut of the cutting inserts, wherein the facet comprises a width of 0.12 to 1.12 inches, wherein a distance between the rotation axis and a closer edge of the facet is less than a distance from the rotation axis to the inner radius of the circular ring, and wherein the rotation axis is offset from the facet being milled on the railway rail by the cutting inserts; traversing the railway rail in situ with the milling cutter while milling the railway rail; controlling the depth of cut of the cutting inserts to a depth no more than 0.040 inches; and controlling the speed of traverse of the milling cutter along the railway rail.
 28. The method of claim 27, comprising controlling the speed of traverse of the milling cutter along the railway rail to speeds greater than 3 mph.
 29. The method of claim 27, comprising controlling the speed of traverse of the milling cutter along the railway rail to speeds greater than 15 mph.
 30. The method of claim 27, wherein the rotation axis of the milling cutter is offset from the facet being milled on the railway rail by a distance that is 35% to 40% of the diameter of the milling cutter.
 31. The method of claim 27, wherein the milling cutter is mounted to a carriage that moves along the railway rail in situ.
 32. The method of claim 27, further comprising: providing a further milling cutter; milling the railway rail with the milling cutters the further milling cutter including a plurality of cutting inserts mounted about a periphery of a cutter face thereof, wherein cutting edges of the cutting inserts of each milling cutter are rotated in different predetermined planes, each predetermined plane corresponding to at least a portion of a desired rail profile.
 33. The method of claim 32, wherein each of the milling cutters is mounted to a carriage that moves along the railway rail in situ.
 34. The method of claim 33, comprising controlling the speed of traverse of the milling cutters along the railway rail to speeds greater than 15 mph.
 35. The method of claim 32, wherein each of the milling cutters is individually mounted to respective spindles, and wherein the milling cutters are individually positionable about the railway rail in situ to mill a plurality of portions of a desired profile on the railway rail in situ.
 36. The method of claim 32, wherein the rotation axis of each of the milling cutters is offset from the respective facet being milled on the railway rail by a distance that is between 35% and 40% of the diameter of the respective milling cutter.
 37. The method of claim 32, wherein the rotation axis of each of the milling cutters is offset from the respective facet being milled on the railway rail by 3 inches to 4.5 inches.
 38. The method of claim 27, wherein the rotation axis of the milling cutter is offset from the facet being milled on the railway rail by 3 inches to 4.5 inches.
 39. A method of milling at least a portion of a profile on a railway rail in situ, the method comprising: rotating a first milling cutter about a first rotation axis; rotating a second milling cutter about a second rotation axis that differs from the first rotation axis; wherein each of the first and second milling cutters comprises a cutter body including a cutter face, and a plurality of cutting inserts mounted around a periphery of the cutter face, each of the plurality of cutting inserts comprising a cutting edge, each cutting edge including two ends, wherein as each milling cutter rotates about its respective rotation axis the ends of the cutting edges of the respective milling cutter define a circular ring comprising an inner radius, defined by inner ends of the cutting edges, and an outer radius, defined by outer ends of the cutting edges; milling a first facet of the profile on the railway rail in situ with the cutting edges of the first milling cutter as the first milling cutter rotates about the first rotation axis while controlling a depth of cut of the cutting inserts of the first milling cutter, wherein a distance between the first rotation axis and a closer edge of the first facet is less than a distance from the first rotation axis to the inner radius of the circular ring formed by the first milling cutter, and wherein the first rotation axis is offset from the first facet being milled on the railway rail by the cutting inserts of the first milling cutter; milling a second facet of the profile on the railway rail in situ with the cutting edges of the second milling cutter as the second milling cutter rotates about the second rotation axis while controlling a depth of cut of the cutting inserts of the second milling cutter, wherein a distance between the second rotation axis and a closer edge of the second facet is less than a distance from the second rotation axis to the inner radius of the circular ring formed by the second milling cutter, wherein the second rotation axis is offset from the second facet being milled on the railway rail by the cutting inserts of the second milling cutter, and wherein cutting edges of the first and second milling cutters rotate in different predetermined planes, each predetermined plane corresponding to at least a portion of the rail profile; traversing the railway rail in situ with the first and second milling cutters while milling the railway rail; and controlling the speed of traverse of the first and second milling cutters along the railway rail.
 40. The method of claim 39, wherein each of the first and second milling cutters are mounted to a carriage that moves along the railway rail in situ.
 41. The method of claim 39, wherein each of the first and second milling cutters is individually mounted to respective spindles, and wherein the milling cutters are individually positionable about the railway rail in situ to mill a plurality of portions of a desired profile on the railway rail in situ. 